Asi071mc

[Gavin1234]

Hi I noticed there’s a couple of people here who have the same camera as me, some even have the same camera and scope. So I thought I’d ask what settings people are using.

Using mainly use my ASI071MC and Esprit 100ED

I use gain at 160.
Usual exposure length is 3 minutes.
I usually set the temp to -15.
On SGP the lowest HFR I can get is about 1.20 at binning 1x1, using my auto focuser.

Hoping you guys would share your settings.

[ChrisV (Chris)]

I have only used this camera at unity gain = 94.

Temperature = -5C. I don't see any point in going lower with this camera

Exposure length = 120sec - my scopes are F4 and F5. I sometime go even lower - 90sec.

At unity gain, 90-120sec subs are swamping read noise heaps and I'm not getting too much star saturation. Accordings to Shiraz's spreadsheet 60 - 120sec is about optimal for this.

So I figure you might be working at too high gain and too long for exposures

[Camelopardalis (Dunk)]

Yeah I’d agree with Chris.

Form maximum dynamic range - referring to your M20 thread - I’d drop the gain down to zero. Might need a few minuted of exposure time, but you should find the star colour more pronounced, or at least, better preserved.

The dark noise of this camera is really negligible, even at 5C.

[Gavin1234]

Ok showing my ignorance of my gear here but if I drop the gain down to zero it automatically shoots at unity gain?

[Camelopardalis (Dunk)]

No. Why would it do anything automatically?!

Zero is lower than unity. There’s nothing special about unity, or any other gain. The dynamic range should be maximised as you approach zero, due to the 14-bit ADC.

[Gavin1234]

So if I put the gain to zero won’t it be too dark?

[ChrisV (Chris)]

No. Have a look at the spces for the camera
Gain0 = 3e- per ADU, Gain160=0.5e- per ADU. So gain0 has about 1/3rd the sentivity of unity gain, and gain160 about twice the sensitivity of unity gain

Just pick a gain to start with - 0 or unity. Better either of these than 160. You'll find 1-2min subs good for unity, and maybe2-3min subs for zero?